<!DOCTYPE html>
<html>
<head>
    <title>电子时钟</title>
    <style>
        .clock {
            font-size: 50px;
            font-family: Arial, Helvetica, sans-serif;
            text-align: center;
            margin-top: 50px;
        }
    </style>
</head>
<body>
    <div class="clock">00:00:00</div>
    <script src="script.js"></script>
</body>
</html>
